/*
 * Copyright 2002-2013 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.security.config.annotation.web.configurers;


import javax.servlet.http.HttpServletRequest;

import org.springframework.security.access.SecurityConfig;
import org.springframework.security.config.annotation.web.HttpSecurityBuilder;
import org.springframework.security.config.annotation.web.configurers.AbstractConfigAttributeRequestMatcherRegistry.UrlMapping;
import org.springframework.security.web.util.matcher.RequestMatcher;


/**
 * Configures non-null URL's to grant access to every URL
 * @author Rob Winch
 * @since 3.2
 */
final class PermitAllSupport {

    public static void permitAll(HttpSecurityBuilder<? extends HttpSecurityBuilder<?>> http, String... urls) {
        for(String url : urls) {
            if(url != null) {
                permitAll(http, new ExactUrlRequestMatcher(url));
            }
        }
    }

    @SuppressWarnings("unchecked")
    public static void permitAll(HttpSecurityBuilder<? extends HttpSecurityBuilder<?>> http, RequestMatcher... requestMatchers) {
        ExpressionUrlAuthorizationConfigurer<?> configurer = http.getConfigurer(ExpressionUrlAuthorizationConfigurer.class);

        if(configurer == null) {
            throw new IllegalStateException("permitAll only works with HttpSecurity.authorizeRequests()");
        }

        for(RequestMatcher matcher : requestMatchers) {
            if(matcher != null) {
                configurer.getRegistry().addMapping(0, new UrlMapping(matcher, SecurityConfig.createList(ExpressionUrlAuthorizationConfigurer.permitAll)));
            }
        }
    }

    private final static class ExactUrlRequestMatcher implements RequestMatcher {
        private String processUrl;

        private ExactUrlRequestMatcher(String processUrl) {
            this.processUrl = processUrl;
        }

        public boolean matches(HttpServletRequest request) {
            String uri = request.getRequestURI();
            String query = request.getQueryString();

            if(query != null) {
                uri += "?" + query;
            }

            if ("".equals(request.getContextPath())) {
                return uri.equals(processUrl);
            }

            return uri.equals(request.getContextPath() + processUrl);
        }

        @Override
        public String toString() {
            StringBuilder sb = new StringBuilder();
            sb.append("ExactUrl [processUrl='").append(processUrl).append("']");
            return sb.toString();
        }
    }

    private PermitAllSupport() {}
}